In English, there are words known as homophones, words that sound the same (or very close to the same), but are spelled differently and mean something different.
True homophones are tricky because there’s nothing different about how we say them. And they trip up even the best writers because if they’re spelled correctly, spellcheck is happy with them! But they are not interchangeable; they mean what they mean.
So (sew), let’s (lets) be (bee) sure (shore) we (wee) know (no) which (witch) is which, OK?
Its = the possessive pronoun: The dog wagged its tail.
It’s = it is: It’s wagging its tail. It has: It’s been nice seeing you!
FYI: Remember, we do use apostrophes in “normal” possessive words, but we do NOT use them in possessive pronouns.
The dog’s ears perked up as it wagged its tail.
Their = the possessive pronoun
There = a place
They’re = they are
They’re reading their books over there.
Yore = in a long-ago time: Rome was a great empire in days of yore.
Your = the possessive pronoun
You’re = you are
You’re going to take your test tomorrow.
The reality is that too many writers blindly trust spellcheck, but that program does only one thing: it checks spelling. It cannot and does not check usage. So if you use the wrong word but spell it correctly …
What other words are you confused about? And no; “confuzzled” isn’t a real word; I made it up. But I think it speaks loudly about how many of us feel about learning a new language, no matter which one it is.